Locking means for telescopically fitted members



March 8, 1966 GRELLSSQN 3,239,243

LOCKING MEANS FOR TELESCOPICALLY FITTED MEMBERS Filed April 1, 1963 2 Sheets-Sheet 1 I NVEN TOR.

4%1MWW March 8, 1966 K. s. GRELLSSON LOCKING MEANS FOR TELESCOPICALLY FITTED MEMBERS 2 Sheets-Sheet 2 Filed April 1, 1963 MWW/ Z Z ZSEL k-v'arraemsr United States Patent 3,239,243 LQCKING MEANS FOR TELESCOPICALLY FITTED MEMBERS Karl Gustav Grelisson, Sollentuna, Sweden, assignor to Ahtiebolaget Electrolux, Stockholm, Sweden, a corporation of fiweden Filed Apr. 1, 1963, Ser. No. 269,618 Claims priority, application Sweden, Apr. 5, 1962, 3,784/ 62 7 Claims. (Cl. 285-7) My invention relates to locking means for telescopically fitted members.

It is an object of my invention to provide an improved locking means of this type for effectively locking telescopically fitted members, and to provide a construction which is simple and inexpensive to manufacture.

Another object of my invention is to provide an improved locking means between an outer hollow member and an inner member telescopically fitted therein in such manner that a force is transmitted directly through the wall of the outer member to firmly clamp the members together. I accomplish this by providing an outer hollow member having a longitudinally extending zone including a wall section which is bendable and bodily movable inward responsive to force applied thereto at its outer surface, and mechanism for effectively applying such force to the zone of the hollow member at such wall section.

Further objects and advantages of the invention will become apparent as the following description proceeds, and the features of novelty which characterize the invention will be pointed out with particularity in the claims annexed to and forming a part of this specification.

For a better understanding of the invention, reference may be had to the following description taken in connection with the accompanying drawings, in which:

FIG. 1 is a side elevational view, partly broken away and in section, of a suction cleaner embodying my invention;

FIG. 2 is an enlarged longitudinal sectional view of parts shown at the front end of the suction cleaner illustrated in FIG. 1;

FIG. 3 is a front elevational view of the suction cleaner shown in FIG. 1;

FIG. 4 is a fragmentary exploded perspective view of parts shown in FIG. 2;

FIGS. 5 and 6 are fragmentary perspective views illustrating different positions of parts shown in FIGS. 1 to 4; and

FIGS. 7 and 8 are fragmentary perspective views similar to FIGS. 5 and 6, respectively, illustrating a modification of the invention.

Referring to the drawing, I have shown my invention as applied to a portable tank-type suction cleaner having a casing 10 which is provided with a handle 11. The front end 12 of the casing 10 is provided with a hollow tubular member 14 which constitutes the air inlet of the cleaner and to which a hollow tubular member 15 is adapted to be connected, the outer and inner tubular members 14 and 15 being formed to fit telescopically one within the other.

The inner tubular member 15 may form part of a wand having an outer free end (not shown) to which a suitable cleaning appliance may be connected and through which air is drawn into the interior of the casing 19 by a motor-fan unit (not shown) therein. Dust entrained in air during a cleaning operation is separated from the air when the latter passes through a dust collector 16, and air from which dust has been removed passes through the dust collector and is discharged through an air outlet 17 at the rear end of the casing 1t 3,239,243 Patented Mar. 8, 1966 As shown in FIG. 2, the inner end zone 14a of the outer tubular member 14 is formed with a tapered bore, and the remainder thereof, including an outer longitudinally extending zone 14b which projects outward from the end wall 12, is formed with a cylindrical bore. The inner tubular member 15 includes a tapered end zone 15a, and the remainder thereof, including the zone 15b disposed within the zone 14b, of the outer tubular mem ber 14, is of cylindrical form. Hence, when the inner tubular member 15 is inserted within the outer tubular member 14, the tapered bore of the inner zone 14a is in the path of movement of the inner tapered zone 15a of the inner tubular member 15 and serves as a stop to limit axial inward movement of the inner tubular member Within the outer tubular member. After the inner tubular member 15 is telescopically fitted within the outer tubular member 14 in the manner just described and shown in FIG. 2, the tubular members may be clamped together by locking means.

In accordance with my invention, at least the longitudinally extending zone 14b of the outer tubular member 14 is formed of elastomeric material and includes an axially extending first wall section 14d and an axially extending second wall section which bridges the first wall section 14d and is bendable and bodily movable inward responsive to force applied thereto at its outer surface, and bodily inward movement of the bendable wall section 14c against the outer surface of the zone 15b of the inner tubular member 15 to firmly clamp the tubular mem-be rs together is effected by mechanism 18 mounted on the end wall 12 of the casing 10.

The mechanism 18 includes a cam element 19 having an arm 20 extending therefrom for manually moving the cam element between inoperative and operative positions shown in FIGS. 5 and 6, respectively. As shown in FIGS. 2 and 4, the cam element 19 includes a front end wall having a rim 21 and a hub 22 extending axially therefrom which are spaced from one another and define a groove 23 of annular form. The end -wall 12 of the casing 10 is provided with a part 24 which projects outward from the end wall and is of annular form. The cam element 319 is mounted on the end wall 12 with the projecting part 24 extending into the groove 23 and forming a circular track on which the cam element is rotatable about an axis parallel to the axis of the outer tubular member 14.

The end wall 12 is formed with an opening 25 which extends theretbrough and is defined in part by the annular-shaped projecting part 24. The hub 22 includes a rearwardly extending portion 22a which extends axially through the end wall opening 25. The hub 22 and its outer projecting portion 22a are formed with an axially extending opening 22b, and the outer portion 22a, which may be referred to as a hollow sleeve, is slotted axially to provide a plurality of elongated fingers 26 having outwardly extending hooks 26a at their rear ends. The hooks 26a function as radially movable catches which are arranged to engage a shoulder or notch 27 formed about the opening 25 at the rear surface of the end wall 12 of the casing.

When the cam element 19 is mounted on the end wall 12 with the hollow sleeve 22b extending through the opening 25, the fingers 26 resiliently flex toward one another and, after passing through the wall opening 25, snap radially outward with the hooks 26a engaging the shoulder 27 to prevent withdrawal of the cam element 19. Hence, the cam element 19 is axially immovable along the axis about which it is rotatable. A pin 28 is introduced into the axially extending opening 22b of the hollow sleeve 2 2a and hub 22 and frietionally held therein to maintain the fingers 26 in their radially outward position with the hooks 26a in engagement with the shoulder or notch 27.

The cam element 19 is rotatable on the circular track 24 between inoperative and operative positions shown in FIGS. 5 and 6, respectively. When the operating handle 20 is in the position shown in FIG. 5, the cam element 19 does not exert force against the outer surface of the zone 14b of the outer tubular member 14, and the inner tubular member 15 can be readily inserted into and withdrawn from the outer tubular member 14. When the operating handle is rotated about 90 in a clockwise direction to the position shown in FIG. 6, the cam element 19, due to its eccentric shape, is rendered operable to exert force against the outer surface of the bendable wall section 140 to bodily move the latter against the outer surface of the zone 15b of the inner wall member 15 and firmly clamp the tubular members together.

In order that the cam element 19 can exert force against the zone 14b of the outer tubular member 14 in such manner that the inward directed force will be concentrated over a limited area of its outer surface and not be unnecessarily distributed over a much larger area, the thickness of the wall section 140 desirably is less than the thickness of the wall section 14d of the outer zone 14b at regions adjacent to and abutting the wall section 140. This may be accomplished by removing material from the outer surface of the outer zone 14b at the wall section 14c so that its outer surface 14c will be essentially flat, as shown in FIGS. 5 and 6. Hence, when the cam element 19 is moved to its operative position to apply force against the outer surface of the wall section 140 of the outer member 14, the section 14c readily responds to the application of such inward force and is easily bent and deformed while the wall section 14d adjacent to the wall section 140 is essentially unaffected by the application of the force, whereby the wall section 140 is bodily moved inward, as indicated at 29 in FIG. 6, to effectively clamp the tubular members together.

At least the outer zone 14b of the outer tubular member 14 is formed of a suitable elastomeric material which will function in the manner described above when force is applied to the outer surface of the wall section 140 by the cam element 19 and its operating arm 20 which, in effect, constitutes a force-multiplying mechanism. The elastomeric material may comprise any suitable resilient substance such as natural or synthetic rubber or other rubber-like plastics. The inner tubular member 15 may be formed of elastomeric material or from a suitable metal, such as steel or aluminum, for example.

In FIGS. 7 and 8 I have shown a modification of my invention, in which parts similar to those shown in the embodiment just described are referred to by the same reference numerals. In FIGS. 7 and 8, the outer zone 114b of the outer tubular member 114 is formed with cuts or slits 30 at the side wall section 1140 which extend axially of the outer tubular member. The cuts or slits 30 are essentially gashes which, after being formed, have no visible or only narrow openings and may extend to the edge of the outer tube zone. Hence, an airtight joint will be obtained when the outer tubular member 114 is clamped to an inner tubular member inserted therein in spite of the cuts or slits 30 in the outer tubular member 114. There may be arranged two cuts or slits 30 at a distance from each other which have the function to localize the region that is bent and deformed when force is applied to the outer tubular member 114, but one centrally disposed cut or slit may function to prevent cracking of the tubular member when deformed. By providing the cuts or slits 30 at the wall section 1140 of the outer tubular member 114, the bending and deformation of the wall section 1140 is promoted when force is applied thereto, so that the tubular members will be effectively clamped together.

In view of the foregoing, it will now be understood that I have provided an improved arrangement for locking telescopically fitted tubular members in which the outer tubular member 14 comprises a longitudinally extending zone A, as shown in FIG. 2. The longitudinally extending zone A includes a first axially extending wall section 14d which extends transversely of the axis of the outer member 14 through a first angle of less than 360 and a seecond axially extending wall section 14c which extends transversely of the axis of the outer member 14 through a second angle which is less than the first angle and connects and bridges the first section, the first and second axially extending wall sections 14d and 140, respectively, of the longitudinally extending zone A forming integrally connected parts of the outer tubular member 14. The first axially extending wall section 14d has curved outer and inner surfaces 14d and 14d. The second wall section is of less thickness than the first wall section 14d and has an essentially flat outer surface 14c which merges with the curved outer peripheral surface 14d of the first Wall section 14d. As explained above, the second wall section 14c is bendable and bodily movable inward responsive to force applied thereto at its outer surface 140'.

As shown in FIG. 2, a portion 12a of the front end wall 12 of the casing 10 serves as a support fixed to a region of the outer tubular member 14 which is axially displaced from the longitudinally extending zone A thereof. The mechanism or means 18 mounts the cam element 19 on the support 12a for angular movement thereon adjacent to the outer surface of the outer tubular member 14 between the inoperative and operative positions shown in FIG. 5 and FIG. 6, respectively. The cam element 19 moves between its inoperative and operative positions in a plane which is transverse to the axis of the outer tubular member 14 and intersects the longitudinally extending zone A thereof. The cam element 19 in its operative position shown in FIG. 6 is effective to exert force against the outer surface of the second axially extending wall section 14c of the longitudinally extending zone of the outer tubular member 14 to move the second wall section 14c bodily inward against the outer surface of the inner member 15 and firmly clamp the members together. The element 19 in its inoperative position shown in FIG. 5 is ineffective to exert sufficient force against the outer surface of the second axially extending wall section 14c of the longitudinally extending zone A of the oute rtubular member 14 to move the second wall section 140 bodily inward against the outer surface of the inner member 15 to clamp the members 14 and 15 together.

Although I have shown and described several embodiments of my invention, I do not wish to be limited to the particular arrangements set forth, and I intend in the following claims to cover all modifications which do rot depart from the spirit and scope of the invention.

I claim:

1. An outer hollow tubular member having an axis and an inner member which telescopically fits within the outer tubular member, the outer tubular member comprising a longitudinally extending zone which includes a first axially extending wall section which extends transversely of the axis of the outer member through a first angle of less than 360 and a second axially extending wall section which extends transversely of the axis of the outer member through a second angle which is less than the first angle and connects and bridges the first axially extending wall section, said first and second wall sections of said longitudinally extending zone forming integrally connected parts of said outer tubular member, the second wall section being bendable and bodily movable inward responsive to force applied thereto at its outer surface, a support fixed to a region of the outer tubular member which is axially displaced from said longitudinally extending zone thereof, an element, means for mounting said element on said support for angular movement thereon adjacent to the outer surface of the outer tubular member between inoperative and operative positions in a plane which is transverse to the axis of the outer tubular member and intersects said longitudinally extending zone thereof, said element in its operative position being efiective to exert force against the outer surface of the second axially extending wall section of said longitudinally extending zone of the outer tubular member to move the second wall section bodily inward against the outer surface of the inner member and firmly clamp the members together, and said element in its inoperative position being inelfective to exert sufiicient force against the outer surface of the second axially extending wall section of said longitudinally extending zone of the outer tubular member to move the second wall section bodily inward against the outer surface of the inner member to clamp the members together.

2. Apparatus as set forth in claim 1 in which said longitudinally extending zone of the outer tubular member is formed with at least one slit which extends axially of said zone with no visible opening to promote bending and inward bodily movement of the second wall section by force applied thereto at its outer surface by said element when it is angularly moved on said support to its operative position.

3. Apparatus as set forth in claim 1 in which the axially extending second wall section of said longitudinally extending zone is of less thickness than the axially extending first Wall section thereof.

4. Apparatus as set forth in claim 1 in which the first axially extending wall section of said longitudinally extending zone of the outer tubular member comprises a wall having curved inner and outer surfaces, the axially extending second wall section of said longitudinally extending zone comprising a wall of less thickness than the first wall section, and the second wall section having a substantially flat outer surface which merges with the curved peripheral outer surface of the first wall section.

5. Apparatus as set forth in claim 4 in which said longitudinally extending zone of said outer tubular member is provided with one or more elongated slits which extend axially of said zone with no visible opening or openings to promote bending and inward bodily movement of the second wall section by force applied thereto at its outer surface by said element when it is angularly moved on said support to its operative position.

6. An outer hollow member and an inner member which telescopically fits Within said outer member, said outer member having a wall section which is bendable and bodily movable inward responsive to force applied thereto at its outer surface, mechanism associated with said outer member which includes an element movable between an inoperative position and an operative position in which said element exerts force against the outer surface of said wall section to bodily move said wall section against the outer surface of said inner member and firmly clamp said members together, said mechanism comprising a support fixed to said outer hollow member and forming therewith a unitary structure, said support comprising a wall having an opening extending between opposing surfaces thereof and a part of annular form projecting from one surface at the opening, said element having a groove of annular form receiving said projecting part and rotatable thereon about an axis between its operative and in operative positions, and means to fasten said element to said wall comprising an elongated member fixed to said element and extending axially therefrom through said opening, said elongated member having a plurality of radially movable catches which engage the opposite surface of said wall about the opening to prevent withdrawal of said element from said projecting part.

7. Apparatus as set forth in claim 6 in which said radially movable catches define a split hollow sleeve, and means including an elongated pin in said sleeve to maintain said catches radially outward in engagement with the opposite surface of said wall.

References Cited by the Examiner UNITED STATES PATENTS 652,644 6/1900 Ross 6 1,174,288 3/ 1916 Rosenfeld 285322 1,918,519 7/ 1933 Clements.

2,120,184 6/1938 Mojonnier 285-358 2,793,055 5/ 1957 Meyerhoefer 285-7 2,817,548 12/1957 Uthemann.

FOREIGN PATENTS 137,897 7/ 1950 Australia. 169,257 9/1921 Great Britain.

CARL W. TOMLIN, Primary Examiner. 

1. AN OUTER HOLLOW TUBULAR MEMBER HAVING AN AXIS AND AN INNER MEMBER WHICH TELESCOPICALLY FITS WITHIN THE OUTER TUBULAR MEMBER, THE OUTER TUBULAR MEMBER COMPRISING A LONGITUDINALLY EXTENDING ZONE WHICH INCLUDES A FIRST AXIALLY EXTENDING WALL SECTION WHICH EXTENDS TRANSVERSELY OF THE AXIS OF THE OUTER MEMBER THROUGH A FIRST ANGLE OF LESS THAN 360* AND A SECOND AXIALLY EXTENDING WALL SECTION WHICH EXTENDS TRANSVERSELY OF THE AXIS OF THE OUTER MEMBER THROUGH A SECOND ANGLE WHICH IS LESS THAN THE FIRST ANGLE AND CONNECTS AND BRIDGES THE FIRST AXIALLY EXTENDING WALL SECTION, SAID FIRST AND SECOND WALL SECTIONS OF SAID LONGITUDINALLY EXTENDING ZONE FORMING INTEGRALLY CONNECTED PARTS OF SAID OUTER TUBULR MEMBER, THE SECOND WALL SECTION BEING BENDABLE AND BODILY MOVABLE INWARD RESPONSIVE TO FORCE APPLIED THERETO AT ITS OUTER SURFACE, A SUPPORT FIXED TO A REGION OF THE OUTER TUBULAR MEMBER WHICH IS AXIALLY DISPLACED FROM SAID LONGITUDINALLY EXTENDING ZONE THEREOF, AND ELEMENT, MEANS FOR MOUNTING SAID ELEMENT ON SAID SUPPORT FOR ANGULAR MOVEMENT THEREON ADJACENT TO THE OUTER SURFACE OF THE OUTER TUBULAR MEMBER BETWEEN INOPERATIVE AND OPERATIVE POSITIONS IN A PLANE WHICH IS TRANSVERSE TO THE AXIS OF THE OUTER TUBULAR MEMBER BER AND INTERSECTS SAID LONGITUDINALLY EXTENDING ZONE THEREOF, SAID ELEMENT IN ITS OPERATIVE POSITION BEING EFFECTIVE TO EXERT FORCE AGAINST THE OUTER SURFACE OF THE SECOND AXIALLY EXTENDING WALL SECTION OF SAID LONGITUDINALLY EXTENDING ZONE OF THE OUTER TUBULAR MEMBER TO MOVE THE SECOND WALL SECTION BODILY INWARD AGAINST THE OUTER SURFACE OF THE INNER MEMBER AND FIRMLY CLAMP THE MEMBERS TOGETHER, SAID ELEMENT IN ITS INOPERATIVE POSITION BEING INEFFECTIVE TO EXERT SUFFICIENT FORCE AGAINST THE OUTER SURFACE OF THE SECOND AXIALLY EXTENDING WALL SECTION OF SAID LONGITUDINALLY EXTENDING ZONE OF THE OUTER TUBULAR MEMBER TO MOVE THE SECOND WALL SECTION BODILY INWARD AGAINST THE OUTER SURFACE OF THE INNER MEMBER TO CLAMP THE MEMBERS TOGETHER. 